1. Field of the Invention
The present invention relates to a rolling bearing apparatus constituted by integrating a sensor and a pulser ring for detecting rotation used in ABS (anti-lock brake system) or the like of an automobile to a seal apparatus referred to as a so-to-speak pack seal and sealing a clearance between inner and outer rings by the seal apparatus integrated with the rotation detector.
The present invention also relates to a rolling bearing apparatus having a rotation detector used in ABS (anti-lock brake system) or the like of an automobile.
2. Description of the Related Art
In a related art, there is a bearing apparatus for rotatably supporting an axle of an automobile relative to a vehicle body which is provided with a rotation detector used in ABS or the like (refer to, for example, Patent Reference 1).
According to the bearing apparatus, a rolling member is interposed between respective raceway surfaces of an inner ring fitted outwardly to the axle and constituting a rotating ring and an outer ring fixed to the vehicle body and constituting a fixed ring and a clearance between the inner and the outer rings is sealed by a seal apparatus.
A rotation detector is constructed by a constitution of detecting a change in a magnetic field of a pulser ring fixed to the inner ring constituting the rotating ring by a sensor and transmitting the detection signal to an electronic circuit of the vehicle body via a harness.
Although there is a sufficient space for installing the sensor on a side of a driven wheel, on a side of a driving wheel, a constant-velocity joint is disposed contiguous to the bearing apparatus and therefore, the sensor is provided by utilizing a small space between the bearing apparatus and the constant-velocity joint.
In another related art, there is a bearing apparatus for rotatably supporting an axle of an automobile relative to a vehicle body which is provided with a rotation detector used in ABS or the like (refer to, for example, Patent Reference 2).
The bearing apparatus is constituted by interposing a rolling member between respective raceway surfaces of an outer ring outwardly fitted to an axle and constituting a rotating ring and an outer ring fixed to a vehicle body and constituting a fixed ring.
A rotation detector is constructed by a constitution of detecting a change in a magnetic field of a pulser ring fixed to the inner ring constituting the rotating ring by a sensor and transmitting the detection signal to an electronic circuit of the vehicle body via a harness.
In another related art, there is a bearing apparatus for rotatably supporting an axle of an automobile relative to a vehicle body which is provided with a rotation detector used in ABS or the like (refer to, for example, Patent Reference 3).
According to the bearing apparatus, a rolling member is interposed between respective raceway surfaces of an outer ring fitted to a wheel side and constituting a rotating ring and an inner ring fixed to a vehicle body side and constituting a fixed ring and a clearance between the inner and the outer rings is sealed by a seal is apparatus.
A rotation detector is constructed by a constitution of detecting a change in a magnetic field of a pulser ring fixed to the outer ring constituting the rotating ring by a sensor and transmitting the detection signal to an electronic circuit of the vehicle body via a harness.
[Patent Reference 1]: JP-A-10-48230
[Patent Reference 2]: JP-A-3-6457
[Patent Reference 3]: JP-A-2000-211311
As a sensor for ABS in recent times, a regular and reverse rotation detecting sensor is used for detection of backward movement on a sloping road, an automatic longitudinal row parking function and the like. However, the regular and reverse rotation detecting sensor is large-sized and therefore, when the sensor is installed at the small space on the side of the driving wheel, the sensor is provided to fix to a knuckle.
Further, the pulser ring is provided to expose to an outer face of the bearing apparatus to be opposed to the regular and reverse rotation detecting sensor fixed to the knuckle.
In this way, the pulser ring and the regular and reverse rotation detecting sensor are provided to expose to outside of the bearing apparatus and there poses a problem of being deficient in hermetically sealing performance and inferior in dust resistance performance.
Further, the regular and reverse rotation detecting sensor is provided separately from the bearing apparatus, further, the pulser ring is provided at the outer face of the bearing apparatus, the exclusive space is large and compact formation has been desired to be able to install the sensor in a smaller space.
Normally, the sensor is fixed to a knuckle and the electronic circuit is provided at the vehicle body. Therefore, since the knuckle is connected to a damper against swinging of the vehicle body in running, vibration of the vehicle body is not transmitted to the knuckle. Therefore, whereas the electronic circuit provided at the vehicle body is vibrated by swinging of the vehicle body, the sensor fixed to the knuckle is not influenced by vibration of the vehicle body. Therefore, there is a concern of disconnecting the harness connecting the sensor and the electronic circuit by vibration of the vehicle body.
Further, a sensor for ABS in recent times is included in a seal apparatus which is mounted to a bearing apparatus and is referred to as a so-to-speak pack seal for space saving formation.
Therefore, when the harness of the sensor is disconnected and the ABS sensor becomes abnormal, there poses a problem that it is necessary to interchange a total of a hub unit including the bearing apparatus, time and labor is taken in maintenance operation and also the cost becomes expensive.
Moreover, a detecting face of the rotation detector and a detected face of the pulser ring are arranged to be opposed to each other, an air gap is needed therebetween, a space for installing the rotation detector is enlarged, as a result, a problem that the bearing apparatus becomes large-sized is posed.
Further, a seal lip of a seal apparatus and the rotation detector are provided to be aligned in an axial direction and a problem that the bearing apparatus becomes large-sized is posed.
Since the bearing apparatus becomes large-sized in this way, compact formation thereof has been desired.